0000000000000705

AUTHOR

Michel Hehn

showing 3 related works from this author

Direct Imaging of Chiral Domain Walls and Néel‐Type Skyrmionium in Ferrimagnetic Alloys

2021

International audience; The evolution of chiral spin structures is studied in ferrimagnet Ta/Ir/Fe/GdFeCo/Pt multilayers as a function of temperature using scanning electron microscopy with polarization analysis (SEMPA). The GdFeCo ferrimagnet exhibits pure right-hand Néel-type domain wall (DW) spin textures over a large temperature range. This indicates the presence of a negative Dzyaloshinskii-Moriya interaction (DMI) that can originate from both the top Fe/Pt and the Co/Pt interfaces. From measurements of the DW width, as well as complementary magnetic characterization, the exchange stiffness as a function of temperature is ascertained. The exchange stiffness is surprisingly mostly const…

Materials scienceSpintronicsCondensed matter physics530 PhysicsSkyrmionDirect imaging02 engineering and technologyType (model theory)021001 nanoscience & nanotechnologyCondensed Matter Physics530 Physik01 natural sciences[PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Electronic Optical and Magnetic MaterialsDomain (software engineering)BiomaterialsFerrimagnetism0103 physical sciencesElectrochemistry[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]chirals ; Neel domain walls ; skyrmioniums ; skyrmions spintronics010306 general physics0210 nano-technologyAdvanced Functional Materials
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Quantum advantage in a molecular spintronic engine that harvests thermal fluctuation energy

2022

Recent theory and experiments have showcased how to harness quantum mechanics to assemble heat/information engines with efficiencies that surpass the classical Carnot limit. So far, this has required atomic engines that are driven by cumbersome external electromagnetic sources. Here, using molecular spintronics, we propose an implementation that is both electronic and autonomous. Our spintronic quantum engine heuristically deploys several known quantum assets by having a chain of spin qubits formed by the paramagnetic Co centers of phthalocyanine (Pc) molecules electronically interact with electron-spin selecting Fe/C60 interfaces. Density functional calculations reveal that transport fluct…

Condensed Matter - Mesoscale and Nanoscale PhysicsMechanics of MaterialsMechanical EngineeringMesoscale and Nanoscale Physics (cond-mat.mes-hall)AucunTermodinàmicaFOS: Physical sciencesGeneral Materials ScienceEnergia
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Direct imaging of chiral domain walls and N\'eel-type skyrmionium in ferrimagnetic alloys

2021

The evolution of chiral spin structures is studied in ferrimagnet Ta/Ir/Fe/GdFeCo/Pt multilayers as a function of temperature using scanning electron microscopy with polarization analysis (SEMPA). The GdFeCo ferrimagnet exhibits pure right-hand N\'eel-type domain wall (DW) spin textures over a large temperature range. This indicates the presence of a negative Dzyaloshinskii-Moriya interaction (DMI) that can originate from both the top Fe/Pt and the Co/Pt interfaces. From measurements of the DW width, as well as complementary magnetic characterization, the exchange stiffness as a function of temperature is ascertained. The exchange stiffness is surprisingly mostly constant, which is explaine…

Condensed Matter - Materials Science
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